Wire electric discharge machine having a control means for keeping the wire electrode to a desired angle

摘要

PROBLEM TO BE SOLVED: To provide a wire electric discharge machine including control means that retains a wire electrode at a desired angle without using a new member for excluding an adverse effect of deformation of a column occurring along with a change in a weight of a reel.SOLUTION: Prior to the beginning of machining, verticality of a wire electrode is adjusted, and a weight Wof a reel at this time is measured and stored. Tilt quantities &thetas;and &thetas;of a wire corresponding to Ware extracted from Table 1. Discharge machining is begun, a reel weight Wis measured, and tilt quantities &thetas;and &thetas;of the wire electrode corresponding to the measured reel weight Ware extracted from the Table 1. According to formula 1, correction quantities dand dfor U and V axes using which the wire electrode is retained vertical are calculated based on d=d×tan(&thetas;-&thetas;) and d=d×tan(&thetas;-&thetas;) (where ddenotes a distance in the vertical direction between upper and lower wire guides). The U and V axes are then moved so that the wire electrode becomes vertical.